Jpn. J. Appl. Phys. 8 (1969) pp. 1563-1568 |Next Article| |Table of Contents|
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Density Effect of X-Ray Emission from Porous Specimens in Quantitative Electron Probe Microanalysis
Department of Applied Physics, Waseda University
(Received June 11, 1969)
Density effect of X-ray emission was found for tablet specimens of various densities. Graphite, Cr2O3, CuO and ZnS, which were less than 1 µm in particle size were used as specimens. The specimen density was changed from about 1 to 4 g/cm3.
Electron probe was made into a circle with a diameter of about 10 µm by defocusing on the specimen surface. The results show that the specimen with lower density always gives lower X-ray emission than that with higher density and X-ray intensity from the specimen with the lowest density becomes 70% to 80% of that from a single crystal. To examine the origin of this density effect, experimental F(χ) curves and a back scattering factor R were measured as functions of the specimen density. The results show that f(χ) curves and R-factors scarcely depend on the specimen density, but F(0) factors greatly depend on it. Thus it is concluded that the stopping power of electrons in porous specimens plays an important rôle to the density effect. Lastly, a procedure of correcting for this effect has been suggested.
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